-LRB- CNN -RRB- She stood there , injured and holding a knife , outside her Florida home .

That image is horrifying enough , but nothing compared to what police say they found inside .

All three of that woman 's children were unresponsive when officers encountered them Friday evening , including a 7-year-old girl who was reported dead soon thereafter , according to the Palm Bay police department . One of them , a 6-year-old boy , died later . A 5-month-old boy is seriously injured .

Their mother , identified by police as Jessica Lacey McCarty , did n't comply to officers ' request that she drop her knife . So officers fired several `` less lethal '' bean bag rounds at her , after which she was taken into custody , according to police .

And on Saturday , Palm Bay police announced on the department 's Facebook page that McCarty was being charged with two counts of murder in connection with her children 's deaths . The 33-year-old woman is also facing an attempted murder charge regarding her infant son , who was in critical condition at a nearby hospital .

After initially being taken to a hospital after suffering what police called `` non-life threatening injuries , '' McCarty was moved to the Brevard County Detention Center , where she 's being held without bond .

She will face a judge within 24 hours to address the charges , according to the Palm Bay post from around midday Saturday .

`` A crime like this is beyond words , '' police Capt. Josh Resh said . `` It is unthinkable that someone could do this to innocent children . ''

Authorities ' first indication of trouble came in a 911 call just before 6 p.m. Friday from a woman claiming to have killed her three children . McCarty 's boyfriend -- the father of one of the children -- placed his own call to police seconds later , after arriving home to the grim scene .

How and why did the children die ? Authorities are waiting on results from an autopsy , scheduled for Sunday , to definitively figure that all out .

`` We are still trying to verify the sequence of events , how and why they occurred , '' Palm Bay police Lt. Mario Augello said . '' ... This is still a very active criminal investigation . ''

Regardless , the episode shook those in the victims ' neighborhood in Palm Bay , which is about 70 miles southeast of Orlando on Florida 's Atlantic coast .

It started with the sirens and about 10 armed officers coming down the street , telling him to get inside , neighbor Davion Lewis CNN affiliate WESH .

But for neighbor Becky Johnson , learning why they had come was even more horrifying .

`` It 's inexcusable , unthinkable , ... shocking , '' Johnson said . `` You think of your own kids . ''

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Police fired `` less lethal '' bean bag rounds at woman with knife after she did n't comply

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An autopsy set for Sunday could help determine how the children died , police say

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3 children are found unresponsive at a home in Palm Bay , on Florida 's East coast